System and method for improved free fall detection

ABSTRACT

An information handling system includes a free fall sensing system having an amplifier and sampling circuit, a sampling data analyzer, a sampling clock duration controller, and a sampling clock generator. The amplifier and sampling circuit is configured to sample data signals from the free fall sensor based on an initial sampling signal and based on a variable sampling signal. The sampling data analyzer is configured to compare a magnitude of sampled data point to a predetermined magnitude, to output an alert signal when the magnitude of the sampled data point is below the predetermined magnitude. The sampling clock duration controller is configured to vary a duration and a frequency of a sampling signal control in response to the alert signal. The sampling clock generator is configured to send a variable sampling signal to the amplifier and sampling circuit in response to the variation of the duration and the frequency of the sampling signal control.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.12/897,328, entitled “System and Method for Improved Free FallDetection,” filed on Oct. 4, 2010, the disclosure of which is herebyexpressly incorporated by reference in its entirety.

FIELD OF THE DISCLOSURE

This disclosure relates generally to information handling systems, andmore particularly relates to system and method for improved free falldetection.

BACKGROUND

As the value and use of information continues to increase, individualsand businesses seek additional ways to process and store information.One option is an information handling system. An information handlingsystem generally processes, compiles, stores, and/or communicatesinformation or data for business, personal, or other purposes. Becausetechnology and information handling needs and requirements can varybetween different applications, information handling systems can alsovary regarding what information is handled, how the information ishandled, how much information is processed, stored, or communicated, andhow quickly and efficiently the information can be processed, stored, orcommunicated. The variations in information handling systems allow forinformation handling systems to be general or configured for a specificuser or specific use such as financial transaction processing, airlinereservations, enterprise data storage, or global communications. Inaddition, information handling systems can include a variety of hardwareand software components that can be configured to process, store, andcommunicate information and can include one or more computer systems,data storage systems, and networking systems.

An information handling system, such as a portable computer, may includea free fall sensor to mitigate damage to a hard disk drive when theportable computer falls. When the free fall sensor detects that theportable computer is experiencing a free fall event, circuits and/ormodules within the portable computer can stop read/write operations forthe hard disk drive and lock down a read/write head of the hard diskdrive to prevent the read/write head from scratching the hard disk driveduring the fall.

BRIEF DESCRIPTION OF THE DRAWINGS

It will be appreciated that for simplicity and clarity of illustration,elements illustrated in the Figures have not necessarily been drawn toscale. For example, the dimensions of some of the elements areexaggerated relative to other elements. Embodiments incorporatingteachings of the present disclosure are shown and described with respectto the drawings presented herein, in which:

FIG. 1 is a block diagram of a free fall sensing system of aninformation handling system;

FIG. 2 is a graph of a plurality of waveforms associated with the freefall sensing system;

FIG. 3 is a graph of an alternative plurality of waveforms associatedwith the free fall sensing system;

FIG. 4 is a graph of another alternative plurality of waveformsassociated with the free fall sensing system;

FIG. 5 is a flow diagram of a method for minimizing false free falldetections; and

FIG. 6 is a block diagram of a general computer system.

The use of the same reference symbols in different drawings indicatessimilar or identical items.

DETAILED DESCRIPTION OF DRAWINGS

The following description in combination with the Figures is provided toassist in understanding the teachings disclosed herein. The followingdiscussion will focus on specific implementations and embodiments of theteachings. This focus is provided to assist in describing the teachingsand should not be interpreted as a limitation on the scope orapplicability of the teachings. However, other teachings can certainlybe utilized in this application.

FIG. 1 shows a free fall sensing system 100 of an information handlingsystem. For purposes of this disclosure, an information handling systemmay include any instrumentality or aggregate of instrumentalitiesoperable to compute, classify, process, transmit, receive, retrieve,originate, switch, store, display, manifest, detect, record, reproduce,handle, or utilize any form of information, intelligence, or data forbusiness, scientific, control, entertainment, or other purposes. Forexample, an information handling system may be a personal computer, aPDA, a consumer electronic device, a network server or storage device, aswitch router or other network communication device, or any othersuitable device and may vary in size, shape, performance, functionality,and price. The information handling system may include memory, one ormore processing resources such as a central processing unit (CPU) orhardware or software control logic. Additional components of theinformation handling system may include one or more storage devices, oneor more communications ports for communicating with external devices aswell as various input and output (I/O) devices, such as a keyboard, amouse, and a video display. The information handling system may alsoinclude one or more buses operable to transmit communications betweenthe various hardware components.

The free fall sensing system 100 includes free fall sensors 104, 106,and 108, an amplifier and sampling module 110, a sampling data analyzer112, a monitor unit 114, a counter timer 116, a counter buffer 118, asampling clock generator 120, and a sampling clock duration controller122. The free fall sensors 104, 106, and 108 are in communication withthe amplifier and sampling module 110, which in turn is in communicationwith the sampling data analyzer 112. The sampling data analyzer 112 isin communication with the monitor unit 114, which in turn is incommunication with the counter timer 116. The monitor unit 114 can be incommunication with the counter buffer 118, or the counter buffer can belocated within the monitor unit. The monitor unit 114 is incommunication with the sampling clock generator 120 and with thesampling clock duration controller 122. The sampling clock durationcontroller 122 can be in communication with the sampling clock generator120, or the sampling clock duration controller 122 can be part of thesampling clock generator 120. The sampling data analyzer 112 is incommunication with a head control circuit 124, which in turn is incommunication with a read/write head 126 of a hard disk drive 128. Eachof free fall sensors 104, 106, and 108 preferably detect motion of theinformation handling system or portable computer 102 along a differentdirectional axis. For example, the free fall sensor 104 can detectmovement along the X-axis, the free fall sensor 106 can detect movementalong the Y-axis, and the free fall sensor 108 can detect movement alongthe Z-axis. In one embodiment, the sensors 104, 106, and 108 may beintegrated into an accelerometer.

During operation, the free fall sensors 104, 106, and 108 can send datasignals to the amplifier and sampling circuit 110 in response todetecting movement of or vibrations in the information handling system102. The amplifier and sampling circuit 110 can take a reading and/or asample of the data signals at a particular sampling rate set by thesampling clock generator 120. The sampling clock duration controller 122can set an initial sampling duration, such that the sampling clockgenerator 120 can provide the amplifier and sampling circuit 110 with aninitial sampling signal that has a fixed frequency and a fixed durationbetween pulses of the initial sampling signal. For example, the initialsampling signal can have a fixed duration between pulses of two and ahalf milliseconds, and a fixed frequency of around four hundred hertz.The amplifier and sampling circuit 110 can sample the data signals fromthe free fall sensors 104, 106, and 108 and determine a magnitude of thesampled data point from the data signals in response to detecting eachpulse of the sampling signal received from the sampling clock generator120.

The amplifier and sampling circuit 110 can send the sampled data pointto the sampling data analyzer 112, which in turn can compare eachmagnitude of the sampled data points to a predetermined magnitude. Thepredetermined magnitude can be a magnitude of a sampled data point thatindicates that the information handling system 102 is experiencing afree fall event. When the magnitude of the sampled data point is belowthe predetermined magnitude the sampling data analyzer 112 can output analert signal. The monitor unit 114 can set the counter buffer 118 to ahigh voltage level and can start the counter timer 116 in response toreceiving the alert signal. When the counter timer 116 is started, themonitor unit 114 can send a vary sampling request signal to the samplingclock duration controller 122. The vary sampling request signal cancause the sampling clock duration controller 122 to vary the samplingduration between the pulses of the sampling signal to slightly more orslightly less than the initial duration. The variation in the durationbetween the pulses can be different between each set of pulses of thesampling signal. The variation in the sampling duration can cause thesampling clock generator 120 to vary when a pulse is generated on thesampling signal. The amplifier and sampling circuit 110 can sample thedata signals from the free fall sensors 104, 106, and 108 at each pulseof the variable sampling signal from the sampling clock generator 120,and can send the sampled data point to the sampling data analyzer 112.

The sampling data analyzer 112 can again compare the magnitude of thesampled data point to the predetermined magnitude, and can continue tosend the alert signal to the monitor unit 116 if the magnitude of eachof the sampled data points is below the predetermined magnitude. Themonitor unit 114 can keep the counter buffer 118 at the high voltagelevel while the magnitude of the sampled data point is below thepredetermined magnitude. However, if the magnitude of the sampled datapoint is above the predetermined magnitude, the monitor unit 114 canclear the counter buffer 118 to a low voltage level.

When the counter timer 116 expires, the monitor unit 114 can determinewhether the counter buffer 118 is at the high voltage level or at thelow voltage level. If the counter buffer 118 is at the low voltage levelwhen the counter timer 116 expires, the monitor unit 114 can determinethat the information handling system 102 is not in free fall, and thatthe free fall sensing system 100 can be reset to await the next datasignals from the free fall sensors 104, 106, and 108. Alternatively, ifthe counter buffer 118 is at the high voltage level when the countertimer 116 expires, the monitor unit 114 can determine that theinformation handling system 102 is in free fall, and can output a lockdown signal to the sampling data analyzer 112. The lock down signal canthen be sent to the head control circuit 124, which in turn can stop aread/write operation of the read/write head 126 and lock the read/writehead in a secure location in preparation for the free fall of theinformation handling system 102. After the read/write head 126 has beenlocked for a predetermined amount of time, the free fall sensing system100 can then be reset to await the next data signals from the free fallsensors 104, 106, and 108.

When the free fall sensors 104, 106, and 108 detect movement, the freefall sensors can output a low level data signal, such that the magnitudeof the data signal is below the predetermined magnitude in the samplingdata analyzer 112. Thus, during a free fall event, the sampled datapoint from the amplifier and sampling circuit 110 can be continuallybelow the predetermined magnitude from the time the counter timer 116starts until the counter timer expires. Therefore, during a free fallevent the sampling data analyzer 112 can lock down the read/write head126 of the hard disk drive 128 when the counter timer 116 expires.

However, a user of the information handling system 102 can utilize aspeaker 130 of the information handling system 102 to generate sound,and the sound may cause vibrations in the free fall sensing system 100.The vibrations in the free fall sensing system 100 from the sound can besubstantially the same frequency as the fixed frequency of the initialsampling signal. If the vibrations in the free fall sensing system 100from the sound are strong enough and if the magnitude of the sampleddata point is below the predetermined level, then the sampling dataanalyzer 112 can detect a false free fall event and can lock down theread/write head 126 of the hard disk drive 128. For example, the speaker130 can be a sub-woofer or the like that is designed to amplify audio ina low frequency range, such as three hundred to six hundred hertz. Ifthe fixed frequency of the initial sampling signal is around fourhundred hertz, the fixed frequency can be within the frequency range ofthe sound from the speaker 130. Thus, the frequency of the amplifiedsound can be sampled by the amplifier and sampling circuit 110, suchthat the magnitude of the sampled data point can be below thepredetermined magnitude when measured by the sampling data analyzer 112.Thus, sound generated by the speaker 130 of the information handlingsystem 102 can cause a false free fall detection if the frequency andduration between pulses of the sampling signal are not varied and aresubstantially equal to that of the sound.

FIG. 2 shows a particular embodiment of a plurality of waveformsassociated with the free fall sensing system 100 when the samplingsignal duration is constantly set at the initial duration. The pluralityof waveforms includes a sound vibrations waveform 202, a counter timerwaveform 204, a sampling signal waveform 206 with a plurality of pulses,and counter buffer waveform 208. The sound vibrations waveform 202 canbe the vibrations caused in the free fall sensor when the user of theinformation handling system 102 is utilizing the speaker 130 to generatesound. The counter timer waveform 204 can be set to a high voltage levelwhen a magnitude of a first sampled data point is detected below thepredetermined magnitude 210, and the counter timer waveform can be setto a low voltage level when the counter time has expired.

The sampling signal waveform 206 preferably has a constant frequency andduration, and can have substantially the same frequency as the soundvibrations waveform 202. The counter buffer waveform 208 can be set to ahigh voltage level when the first sampled data point is detected belowthe predetermined magnitude 210. If the frequency of sampling signalwaveform 206 is substantially equal to the frequency of the soundvibrations waveform 202, as shown in FIG. 2, the sampling data can bebelow the predetermined magnitude 210 at each pulse of the samplingsignal waveform. Thus, when the counter timer expires, as indicated bydashed line 212, the counter timer waveform 204 is set to the lowvoltage level, and the counter buffer waveform 208 can still be set tothe high voltage level. In this situation, when the counter bufferwaveform 208 is at the high voltage level a false free fall eventdetection can be created. The sampling data analyzer 112 can then causethe read/write head 126 to be improperly locked down, based on the falsefree fall detection.

FIG. 3 shows a particular embodiment of a plurality of waveformsassociated with the free fall sensing system 100 when sampling clockduration controller 122 varies the sampling signal duration. Theplurality of waveforms includes a sound vibrations waveform 302, acounter timer waveform 304, a sampling signal waveforms 306 and 314 eachwith a plurality of pulses, and counter buffer waveform 308. The soundvibrations waveform 302 can be the vibrations caused in the free fallsensor when the user of the information handling system 102 is utilizingthe speaker 130 to generate sound. The counter timer waveform 304 can beset to a high voltage level when a magnitude of a first sampling data isdetected below the predetermined magnitude 310, and can be set to a lowvoltage level when the counter timer expires at line 312. The samplingsignal waveform 306 preferably has a number of pulses with a constantfrequency and a constant duration between the pulses, and the frequencyand duration between the pulses may have substantially the samefrequency as the sound vibrations waveform 302. However, the samplingsignal waveform 314 preferably has a number of pulses with a variablefrequency and a variable duration between the pulses, and the frequencyand duration between the pulses can vary from the frequency and durationof the sampling signal waveform 306 and the sound vibrations waveform302.

The sampling signal waveform 314 is preferably used when a magnitude ofa first sampled data point is below the predetermined magnitude 310 hasbeen detected. The counter buffer waveform 308 can be set to a highvoltage level when the magnitude of the first sampled data point isdetected below the predetermined magnitude 310. The sound vibrationswaveform 302 can then be sampled based on the sampling signal waveform314 with the variable frequency and the variable duration between thepulses of the sampling signal waveform. When the magnitude of thesampled data point of the sound vibrations waveform 302 is above thepredetermined magnitude 310, the counter buffer 308 is preferably set toa low voltage level. Thus, when the counter timer expires, as indicatedby the dashed line 312, the counter timer waveform 304 is set to a lowvoltage level, and the counter buffer waveform 308 can be at the lowvoltage level indicating that a free fall event has not been detected.The sampling data analyzer 112 can then preferably not lock down theread/write head 126, based on the counter buffer waveform 308 having thelow voltage level.

FIG. 4 shows a particular embodiment of a plurality of waveformsassociated with the free fall sensing system 100 when sampling clockduration controller 122 varies the sampling signal duration. Theplurality of waveforms includes a free fall detection waveform 402, acounter timer waveform 404, a sampling signal waveforms 406 and 414, andcounter buffer waveform 408. The free fall detection waveform 402 can bereceived from one of the free fall sensors 104, 106, or 108. The countertimer waveform 404 can be set to a high voltage level when a magnitudeof a first sampling data is detected below the predetermined magnitude410, and can be set to a low voltage level when the counter timerexpires at line 412. The sampling signal waveform 406 preferably has anumber of pulses with a constant frequency and a constant durationbetween the pulses, and the frequency and duration between the pulses.However, the sampling signal waveform 414 preferably has a number ofpulses with a variable frequency and a variable duration between thepulses, and the frequency and duration between the pulses can vary fromthe frequency and duration of the sampling signal waveform 406.

The counter buffer waveform 408 can be set to a high voltage level whenthe magnitude of the first sampled data point is detected below thepredetermined magnitude 410. If the information handling system 102 ismoving in one of the directions of the free fall sensors, the free falldetection waveform 402 is preferably continually below the predeterminedmagnitude 410. Thus, when the counter timer expires, as indicated bydashed line 412, the counter timer waveform 404 is set to a low voltagelevel, and the counter buffer waveform 408 can still be set to the highvoltage level indicating a free fall event. The sampling data analyzer112 can then lock down the read/write head 126, based on the counterbuffer waveform 408 having the high voltage level.

FIG. 5 shows a flow diagram of method 500 for minimizing false free falldetections. At block 502, free fall sensor system is initialized. Thefree fall sensor system can receive free fall sensor data from any of anumber of sensors that detect movement in an information handling system102. The sensors can also send false free fall sensor data in responseto vibrations of the information handling system 102 and the free fallsensors from sound generated in the information handling system. Thefree fall sensor data is sampled at block 504. The free fall sensors canbe sampled in response to a number of pulses in a sampling signal. Atblock 506, a determination is made whether a magnitude of the sampleddata point is within an active region. The active region can be set suchthat a movement of the information handling system 102 can cause themagnitude of the sampled data point to enter the active region. In oneembodiment, the active region can be when the magnitude of the sampleddata point is below a predetermined magnitude. In another embodiment,the active region can be when the magnitude of the sampled data point isabove a predetermined magnitude.

When the magnitude of the sampled data point is not within the activeregion, the flow can repeat as stated above at block 504. When themagnitude of the sampled data point is within the active region, acounter timer and a counter buffer are both set to a high voltage levelat block 508. At block 510, the free fall data is sampled based on asampling signal having a variable frequency and a variable durationbetween the pulses of the sampling signal. The variable duration betweenthe pulses can be more or less that the fixed duration between thepulses. At block 512, a determination is made whether the magnitude ofthe sampled data point taken based on the variable sampling signal iswithin the active region. If the magnitude of the sampled data point isnot within the active region, the counter buffer is cleared at block514. The counter buffer can be cleared by setting the counter buffer toa low voltage level. At block 516, a determination is made whether thecounter timer has expired. If the counter timer has not expired the flowrepeats as stated above at block 510. However, if the counter timer hasexpired, a determination is made whether the counter buffer is clearedat block 518.

If the counter buffer is not cleared, a read/write head of a hard diskdrive is locked down at block 520. At block 522, the counter timer andthe counter buffer are cleared. When the counter timer and the counterbuffer are clear, the system resets and the flow repeats as stated aboveat block 504. Referring back to block 512, if the sampled data point iswithin the active region, a determination is made whether the countertimer has expired at block 524. If the counter timer not has expired theflow repeats as stated above at block 510. If the counter timer hasexpired the flow repeats as stated above at block 518.

FIG. 6 shows an illustrative embodiment of a general computer system 600in accordance with at least one embodiment of the present disclosure.The computer system 600 can include a set of instructions that can beexecuted to cause the computer system to perform any one or more of themethods or computer based functions disclosed herein. The computersystem 600 may operate as a standalone device or may be connected suchas using a network, to other computer systems or peripheral devices.

In a networked deployment, the computer system may operate in thecapacity of a server or as a client user computer in a server-clientuser network environment, or as a peer computer system in a peer-to-peer(or distributed) network environment. The computer system 600 can alsobe implemented as or incorporated into various devices, such as apersonal computer (PC), a tablet PC, a set-top box (STB), a personaldigital assistant (PDA), a mobile device, a palmtop computer, a laptopcomputer, a desktop computer, a communications device, a wirelesstelephone, a land-line telephone, a control system, a camera, a scanner,a facsimile machine, a printer, a pager, a personal trusted device, aweb appliance, a network router, switch or bridge, or any other machinecapable of executing a set of instructions (sequential or otherwise)that specify actions to be taken by that machine. In a particularembodiment, the computer system 600 can be implemented using electronicdevices that provide voice, video or data communication. Further, whilea single computer system 600 is illustrated, the term “system” shallalso be taken to include any collection of systems or sub-systems thatindividually or jointly execute a set, or multiple sets, of instructionsto perform one or more computer functions.

The computer system 600 may include a processor 602 such as a centralprocessing unit (CPU), a graphics processing unit (GPU), or both.Moreover, the computer system 600 can include a main memory 604 and astatic memory 606 that can communicate with each other via a bus 608. Asshown, the computer system 600 may further include a video display unit610, such as a liquid crystal display (LCD), an organic light emittingdiode (OLED), a flat panel display, a solid state display, or a cathoderay tube (CRT). Additionally, the computer system 600 may include aninput device 612, such as a keyboard, and a cursor control device 614,such as a mouse. The computer system 600 can also include a disk driveunit 616, a signal generation device 618, such as a speaker or remotecontrol, and a network interface device 620.

In a particular embodiment, as depicted in FIG. 6, the disk drive unit616 may include a computer-readable medium 622 in which one or more setsof instructions 624 such as software, can be embedded. Further, theinstructions 624 may embody one or more of the methods or logic asdescribed herein. In a particular embodiment, the instructions 624 mayreside completely, or at least partially, within the main memory 604,the static memory 606, and/or within the processor 602 during executionby the computer system 600. The main memory 604 and the processor 602also may include computer-readable media. The network interface device620 can provide connectivity to a network 626, e.g., a wide area network(WAN), a local area network (LAN), or other network.

In an alternative embodiment, dedicated hardware implementations such asapplication specific integrated circuits, programmable logic arrays andother hardware devices can be constructed to implement one or more ofthe methods described herein. Applications that may include theapparatus and systems of various embodiments can broadly include avariety of electronic and computer systems. One or more embodimentsdescribed herein may implement functions using two or more specificinterconnected hardware modules or devices with related control and datasignals that can be communicated between and through the modules, or asportions of an application-specific integrated circuit. Accordingly, thepresent system encompasses software, firmware, and hardwareimplementations.

In accordance with various embodiments of the present disclosure, themethods described herein may be implemented by software programsexecutable by a computer system. Further, in an exemplary, non-limitedembodiment, implementations can include distributed processing,component/object distributed processing, and parallel processing.Alternatively, virtual computer system processing can be constructed toimplement one or more of the methods or functionality as describedherein.

The present disclosure contemplates a computer-readable medium thatincludes instructions 624 or receives and executes instructions 624responsive to a propagated signal, so that a device connected to anetwork 626 can communicate voice, video or data over the network 626.Further, the instructions 624 may be transmitted or received over thenetwork 626 via the network interface device 620.

While the computer-readable medium is shown to be a single medium, theterm “computer-readable medium” includes a single medium or multiplemedia, such as a centralized or distributed database, and/or associatedcaches and servers that store one or more sets of instructions. The term“computer-readable medium” shall also include any medium that is capableof storing, encoding or carrying a set of instructions for execution bya processor or that cause a computer system to perform any one or moreof the methods or operations disclosed herein.

In a particular non-limiting, exemplary embodiment, thecomputer-readable medium can include a solid-state memory such as amemory card or other package that houses one or more non-volatileread-only memories. Further, the computer-readable medium can be arandom access memory or other volatile re-writable memory. Additionally,the computer-readable medium can include a magneto-optical or opticalmedium, such as a disk or tapes or other storage device to capturecarrier wave signals such as a signal communicated over a transmissionmedium. A digital file attachment to an e-mail or other self-containedinformation archive or set of archives may be considered a distributionmedium that is equivalent to a tangible storage medium. Accordingly, thedisclosure is considered to include any one or more of acomputer-readable medium or a distribution medium and other equivalentsand successor media, in which data or instructions may be stored.

Although only a few exemplary embodiments have been described in detailabove, those skilled in the art will readily appreciate that manymodifications are possible in the exemplary embodiments withoutmaterially departing from the novel teachings and advantages of theembodiments of the present disclosure. Accordingly, all suchmodifications are intended to be included within the scope of theembodiments of the present disclosure as defined in the followingclaims. In the claims, means-plus-function clauses are intended to coverthe structures described herein as performing the recited function andnot only structural equivalents, but also equivalent structures.

What is claimed is:
 1. An information handling system comprising: a freefall sensor configured to detect movement in the information handlingsystem; an amplifier and sampling circuit in communication with the freefall sensor, the amplifier and sampling circuit configured to sampledata signals from the free fall sensor based on an initial samplingsignal and based on a variable sampling signal; a sampling data analyzerin communication with the amplifier and sampling circuit, the samplingdata analyzer configured to compare a magnitude of a sampled data pointto a predetermined magnitude and to output an alert signal when themagnitude of the sampled data point is below the predeterminedmagnitude; and a sampling clock generator in communication with theamplifier and sampling circuit, the sampling clock generator configuredto send the initial sampling signal to the amplifier and samplingcircuit, and to send the variable sampling signal to the amplifier andsampling circuit in response to the alert signal, wherein the variablesampling signal has different frequencies and different durations thatvary between different pairs of pulses of the variable sampling signal.2. The information handling system of claim 1 further comprising: aread/write head coupled to the sampling data analyzer, the read/writehead configured to suspend read/write operations and lock down inresponse to a lock down signal from the sampling data analyzer; and ahard disk drive in communication with the read/write head, the hard diskdrive configured to store data associated with the read/write operationsof the read/write head.
 3. The information handling system of claim 2further comprising: a head control circuit in communication with thesampling data analyzer and the read/write head, the head control circuitconfigured to cause the read/write head to lock down in response to thelock down signal from the sampling data analyzer.
 4. The informationhandling system of claim 3 wherein the sampling data analyzer is furtherconfigured to output the lock down signal when the counter buffer is atthe high voltage level when a counter timer expires.
 5. The informationhandling system of claim 1 further comprising: a speaker in acousticalcommunication with the free fall sensor, the speaker configured toamplify audio in a low frequency range.
 6. The information handlingsystem of claim 5 wherein the low frequency range is substantially equalto the initial frequency of the sampling signal.
 7. The informationhandling system of claim 1 wherein the second duration between thesecond plurality of pulses of the variable sampling signal is more thanthe first duration between the first plurality of pulses of the initialsampling signal.
 8. The information handling system of claim 1 whereinthe second duration between the second plurality of pulses of thevariable sampling signal is less than the first duration between thefirst plurality of pulses of the initial sampling signal.
 9. A methodfor preventing a false free fall detection in a free fall sensing systemof an information handling system, the method comprising: receiving adata signal from a free fall sensor; sampling the data signal based onan initial sampling signal; determining that a first magnitude of afirst sampled data point from the data signal is within an activeregion, wherein the first sampled data point is based on a firstplurality of pulses in the initial sampling signal; sampling the datasignal based on a variable sampling signal in response to the firstsampled data point being within the active region; determining whether asecond magnitude of a second sampled data point is within the activeregion, wherein the second sampled data point is based on a secondplurality of pulses in the variable sampling signal, wherein thevariable sampling signal has different frequencies and differentdurations that vary between different pairs of pulses of the variablesignal; and locking down a read/write head of a hard disk drive in theinformation handling system in response to the second sampled data pointbeing within the active region.
 10. The method of claim 9 furthercomprising: starting a counter timer in response to the alert signal;setting a counter buffer to a high voltage level in response to thealert signal; sending a vary sampling request to a sampling clockduration controller; and creating the variable sampling signal based onthe vary sampling request.
 11. The method of claim 9 wherein the datasignal indicates movement in the information handling system or thefalse free fall detection.
 12. The method of claim 9 wherein the falsefree fall detection is based on vibrations in the information handlingsystem from sound generated in the information handling system.
 13. Themethod of claim 9 wherein the initial sampling signal has a fixedfrequency and a fixed duration between the first plurality of pulses ofthe initial sampling signal.
 14. The method of claim 9 wherein the firstmagnitude of the first sampled data point from the data signal is withinthe active region when the first magnitude of the first sampled datapoint is below a predetermined magnitude.
 15. The method of claim 9wherein the first magnitude of the first sampled data point from thedata signal is within the active region when the first magnitude of thefirst sampled data point is above a predetermined magnitude.
 16. Amethod for preventing a false free fall detection in a free fall sensingsystem of an information handling system, the method comprising:receiving a data signal from a free fall sensor; sampling the datasignal based on an initial sampling signal, wherein the initial samplingsignal has a fixed frequency and a fixed duration between a firstplurality of pulses of the initial sampling signal; determining that afirst magnitude of a first sampled data point from the data signal isbelow a predetermined magnitude, wherein the first sampled data point isbased on the first plurality of pulses in the initial sampling signal;sending an alert signal to a monitor unit when the first magnitude ofthe first sampled data point is below the predetermined magnitude;creating a variable sampling signal in response to the alert signal;sampling the data signal based on the variable sampling signal inresponse to the alert signal; determining whether a second magnitude ofa second sampled data point is below the predetermined magnitude,wherein the second sampled data point is based on the second pluralityof pulses in the variable sampling signal, wherein the variable samplingsignal has different frequencies and different durations that varybetween different pairs of pulses of the variable signal; determiningwhether a counter timer has expired; and locking down a read/write headof a hard disk drive in the information handling system in response tothe second sampled data point being below the predetermined magnitudewhen the counter timer has expired.
 17. The method of claim 16 furthercomprising: starting the counter timer in response to the alert signal;and setting a counter buffer to a high voltage level in response to thealert signal.
 18. The method of claim 16 wherein the data signalindicates movement in the information handling system or the false freefall detection.
 19. The method of claim 16 wherein the false free falldetection is based on vibrations in the information handling system fromsound generated in the information handling system.
 20. The method ofclaim 16 wherein the first magnitude of the first sampled data pointfrom the data signal is within the active region when the firstmagnitude of the first sampled data Hpoint is below the predeterminedmagnitude.